The stabilization of enzymatic activity is a standing problem in all areas of technology where enzymes are likely to be applied. Stability in this sense stands for resistance to decrease in enzymatic activity prior to usage, e.g., under storage conditions. Concurrently, the enhancement of enzymatic activity has as well received careful attention. Stability and activity problems of compositions containing enzyme components are thought to find their origin in the rather complicated enzyme structure itself. In any event problems become most important when the enzyme-containing composition or additive is formulated with water or is used in aqueous solutions.
Prior art reference representative of the efforts spent to cope with the problems described above include the following. From an article by M. Ceska, EXPERIENTIA, No. 27, 7 pages 767-68, it is known that the activity of certain enzymes may be enhanced through the presence of certain water-soluble nonionic polymers such as dextrans and polyethyleneglycols. Said enhancement is apparently limited to enzymes which catalyze reactions involving high molecular weight substrates or substrates which are known to form multiple attachments with enzymes. Weetal, BIOCHIMICA ET BIOPHYSICA ACTA, 212 (1970) pages 1-7, describes the possibility of increasing the storage stability of water-insoluble enzymes by covalently attaching these enzymes to organic and inorganic carriers. Examples of suitable organic carriers include polyamino-polystyrene, cellulose and polyamino acids. Lilly, et al., THE CHEMICAL ENGINEER, January-February 1968, pages 12-18, refers to enhanced stability characteristics of enzymes by attaching said enzymes to water-insoluble polymers such as cellulose derivatives.
U.S. Pat. No. 3,639,213, Ginger, et al., teaches that streptokinase with increased stability can be obtained by covalently bonding said enzyme to a carbohydrate support. Suitable carbohydrates include cellulose, dextran, starch, dextrins and other polysaccharides having a well-defined molecular weight. U.S. Pat. No. 3,539,450, Deutsch, relates to the stabilization of enzymes by means of certain polyhydric compounds, preferably mannitol, sorbitol, lactose or polyvinyl alcohol.
It is a main object of this invention to provide enzyme containing compositions having improved stability and activity when employed in aqueous media.
It is another object of this invention to provide a method for more beneficially employing enzymes in solution by co-dissolving said enzymes in an essentially aqueous medium together with aminated polysaccharide.
It is still another object of this invention to provide detergent compositions with stabilized and enhanced proteolytic, lipolytic, and amylolytic activity.
It is a further object of this invention to provide detergent compositions capable of exerting enhanced enzymatic activity comprising organic surface-active agents, enzymes and aminated polysaccharide.
The above and other objects are now attained by codissolving in an essentially aqueous medium an enzymatic ingredient in combination with well-defined aminated polysaccharides. Additional objects are met by formulating detergent compositions comprising enzymes, surface-active agents, and well-defined aminated polysaccharides.